There is considerable commercial interest in simple, disposable, self-contained devices for performing biochemical diagnostic assays in extra-laboratory situations. Ideally such devices should avoid any need for complex manual procedures, such as a timed sequence of reagent additions to an analyte, and so be suitable for use by lay persons.
According to Patent Specification WO90/11519 such devices can be of a kind comprising first and second liquid flow channels of porous materials leading from a respective pair of channel ends to a common site, which channels are operable to transfer liquid by capillary flow to the common site in sequentially timed manner following simultaneous application of the liquid to the pair of channel ends.
However, while Specification WO90/11519 describes a variety of particular devices of this kind, they are largely suited to carrying out a single analytical procedure. In contrast there are many situations in which it is desirable to perform plural procedures simultaneously and there would be advantage in a multiple device of integrated form making available such a performance.